DNA analysis is a relatively new field of science as the structure of DNA was only discovered in 1953, by Rosalind Franklin, James Watson and Francis Crick, while Kay Mullis first developed the PCR in 1983 and Sir Alec Jeffreys developed the RFLP technique in 1984 (McDonald & Lehman 2012).
DNA is made of two twisting strands of polymers held together by hydrogen bonds formed between nucleotides (McDonald & Lehman 2012). The differences in the arrangements of the bp is what makes people look different, this also gives each person a unique DNA pattern (McDonald & Lehman 2012).
DNA double helix
Procedures have changed greatly over the last 30 years, through the advancement of technology and the requirements of the legal system (Mountain 2011). In the 1990’s the use of STRs became the norm for DNA profiling as it allowed the use of smaller repeat units, 2 to 7 bp in length, as compared to the previously used AFLPs, which used 16 bp (McDonald & Lehman 2012).
A history of DNA in regards to forensic use
The first commercial kit for PCR of AFLPs was manufactured in California in 1990 and the STR commercial kit replaced the AFLP kit in the late 1990’s (McDonald & Lehman 2012). The STR kits combined the process of amplification and labelling using fluorescent primers, while the availability of these commercial kits lead to the regular use of DNA profiling in forensic labs (McDonald & Lehman 2012).
The determination of gender is often essential in the identification of human remains and the ability to do this through DNA analysis was discovered in 1992, first through the amelogenin locus, where males are 6 bp shorter than females, then through the discovery that mtDNA has a maternal inheritance, which can be detected in the hair shaft not just in the root or bulb (McDonald & Lehman 2012).
DNA analysis is a relatively new field of science as the structure of DNA was only discovered in 1953, by Rosalind Franklin, James Watson and Francis Crick, while Kay Mullis first developed the PCR in 1983 and Sir Alec Jeffreys developed the RFLP technique in 1984 (McDonald & Lehman 2012).
DNA is made of two twisting strands of polymers held together by hydrogen bonds formed between nucleotides (McDonald & Lehman 2012). The differences in the arrangements of the bp is what makes people look different, this also gives each person a unique DNA pattern (McDonald & Lehman 2012).
Procedures have changed greatly over the last 30 years, through the advancement of technology and the requirements of the legal system (Mountain 2011). In the 1990’s the use of STRs became the norm for DNA profiling as it allowed the use of smaller repeat units, 2 to 7 bp in length, as compared to the previously used AFLPs, which used 16 bp (McDonald & Lehman 2012).
The first commercial kit for PCR of AFLPs was manufactured in California in 1990 and the STR commercial kit replaced the AFLP kit in the late 1990’s (McDonald & Lehman 2012). The STR kits combined the process of amplification and labelling using fluorescent primers, while the availability of these commercial kits lead to the regular use of DNA profiling in forensic labs (McDonald & Lehman 2012).
The determination of gender is often essential in the identification of human remains and the ability to do this through DNA analysis was discovered in 1992, first through the amelogenin locus, where males are 6 bp shorter than females, then through the discovery that mtDNA has a maternal inheritance, which can be detected in the hair shaft not just in the root or bulb (McDonald & Lehman 2012).
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